Functionalities of a hearing device become increasingly advanced. Wireless communication between a hearing device and external devices, such as hearing device fitting apparatus, tablets, smart phones and remote controllers, has evolved. A wireless communication interface of a hearing device uses an open standard-based interface. However, this poses many challenges in terms of security. A hearing device may assume any incoming data as legitimate, and may allow memory to be written or changed by an unauthorized party. Any such attacks may result in a malfunction of the hearing aid, or a battery exhaustion attack.